排序方式： 共有3条查询结果，搜索用时 2 毫秒
1
1.
魁蚶(Scapharca broughtonii)半乳糖凝集素(SbGal)基因cDNA的克隆及表达分析 总被引：3，自引：2，他引：1
半乳糖凝集素(Galectin)作为动物凝集素家族的一员,是一种重要的免疫因子,在脊椎动物和无脊椎动物中都参与了重要的免疫防御反应。为明确魁蚶(Scapharca broughtonii)半乳糖凝集素基因的结构特征、组织分布及其对病原菌刺激的免疫反应规律,本研究从构建的魁蚶转录组文库中筛选得到半乳糖凝集素基因部分序列,通过c DNA末端快速扩增(rapid amplication of c DNA ends,RACE)技术获得该基因c DNA全长序列(命名为Sb Gal)。序列和结构分析表明,该c DNA全长3120bp,编码554个氨基酸,是一个含有4个糖识别结构域(CRD)的且在双壳贝类中较为独特的半乳糖凝集素;预测蛋白的分子量(Mw)为63.3158 k Da,理论等电点(p I)为4.99。同源性及系统分析表明,Sb Gal基因与美洲牡蛎、合浦珠母贝、海湾扇贝galectin的同源性分别为70%、65%、46%,Sb Gal基因四个CRD彼此的相似性为36%—41%。实时荧光定量PCR(q RT-PCR)结果表明:Sb Gal m RNA在魁蚶血细胞、斧足、闭壳肌、外套膜、鳃和肝胰腺中均有表达,血细胞中的表达量最高,在肝胰腺中的表达量最低;注射鳗弧菌后,相对于对照组,Sb Gal基因在所检测的每个组织中m RNA水平上的表达量都显著上调(P0.01),而且表达量具有显著的时间依赖性和瞬时表达趋势,呈现先升高后降低的趋势。 相似文献
2.
Lectins are sugar-specific binding proteins or glycoproteins that play important physiological roles in cellular recognition and regulation. And they are also valuable in medicine and pharmacy. Tubeworm is the representative species around the hydrothermal vent in the deep sea. They have developed unique mechanisms to adapt to the harsh environment. In this study, a 1 092 bp c DNA, designed as rpgal, was first cloned and characterized from the tubeworm Ridgeia piscesae. Sequence analysis showed that RPGAL had low homology with the known galectin. And it had two homologous carbohydrate-recognition domains, which is the characteristic of the tandem-repeat type galectins. The RPGAL was successfully recombinant expressed in Escherichia coli and purified. Analysis of biological activity revealed that RPGAL was metal ion independent and it could agglutinate all the vertebrate erythrocytes tested. It was stable at 10–50°C and p H 5–10. And the hemagglutinating activity of RPGAL was strongly inhibited by D-Lactose and lipopolysaccharide. Although RPGAL had no effect on the microorganisms tested, it showed anti-tumor activity towards He La cells and HT1080 cells, which was accomplished by apoptosis. The study demonstrated that RPGAL was a novel galectin and provided a potential candidate for therapy of anti-tumor. 相似文献
3.
三疣梭子蟹(Portunus trituberculatus)半乳糖凝集素PtGAL的基因克隆与原核重组表达 总被引：1，自引：0，他引：1
半乳糖凝集素(Galectin)是动物凝集素家族的一员,在脊椎动物和无脊椎动物中都参与了重要的免疫防御反应,是一种重要的免疫因子。通过RT-PCR和RACE技术克隆获得了三疣梭子蟹(Portunus trituberculatus)半乳糖凝集素基因全长,并命名为PtGal。该基因全长875bp,开放阅读框为669bp,编码222个氨基酸,包含一个糖识别结构域CRD(位于16—142位氨基酸),预测蛋白的分子量(Mw)为23529.4Da,理论等电点(p I)为5.21。同源性比对结果显示,PtGal编码的氨基酸序列与中华绒螯蟹、南美白对虾、日本囊对虾galectin的同源性分别为77%、66%、58%。实时荧光定量PCR(qRT-RCR)结果表明,PtGal在三疣梭子蟹肝胰腺、肌肉、肠、胃、鳃、心脏、性腺中都有表达,其中在性腺中的表达量最高,在肝胰腺中的表达量最低,但人工感染溶藻弧菌(Vibrio alginolyticus)后,肝胰腺的表达呈先升高后降低的趋势。利用原核表达系统对三疣梭子蟹PtGal进行了重组表达,并通过纯化复性获得了重组目的蛋白rPtGal,ELISA检测rPtGal与不同细菌及真菌的结合活性,结果表明,该重组蛋白与革兰氏阳性菌、阴性菌和真菌均有较强的结合。本研究为进一步深入研究三疣梭子蟹半乳糖凝集素的功能奠定了基础。 相似文献
1